Re: Swapping characters in a word inside elisp code

[uzibalqa]

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------- Original Message -------
On Saturday, July 29th, 2023 at 6:03 AM, uzibalqa <uzibalqa@proton.me> wrote:


> I have a word and want to swap characters at position i with position j.
> 
> What would be a good way to do this ? Would I need to change structure
> (to array, vector or some other thing) ?
 
I have done it this way, but it fails when p > q 

How can I solve this ?

(defun cswap (wstr p q)
  "Replace characters in WSTR at positions P and Q."

  (let ( (char1 (elt wstr p))
         (char2 (elt wstr q)) )

    (if (and char1 char2)
        (concat (substring wstr 0 p)
                (char-to-string char2)
                (substring wstr (+ p 1) q)
                (char-to-string char1)
                (substring wstr (+ q 1)))) ))